Furnace roof construction



Jan. 16, 1940. D. w. SQTEWART I 2,187,669

FURNACE ROOF CONSTRUCTION Filed Aug. 21, 1956 |NVENTOR= D. W- STEWART B) ATT RN E Y.

Patented Jan. 16, 1940 2,187,669 FURNACE ROOF CONSTRUCTION Daniel Wallace Stewart, Montreal,

Quebec,

Canada, assignor to Canadian Refractories Limited, Montreal, Quebec, Canada Application August 21, 1936, Serial No. 97,187 In Canada August 12, 1936 7 Claims.

This invention relates to furnace roof construction and is; particularly directed to the construction and suspension of basic or neutral brick units for such roofs.

In the production, refinement and other treatment of various metals the construction and maintenance of the roof of the furnace employed constitutes a substantial element in the cost of such operations. Many proposals have been 10 made for reducing such cost and increasing the efficiency of operation of roofs of this character. For example, sockets have been formed in, or

lugs on, the brick for receiving ,the suspending means and the adjoining faces of brick have been corrugated to receive and hold a suspending metal plate. Brick for furnace wall construction have been encased in metal shields which completely or partially surround the sides of the brick. Brick for use in furnace arched roofs have been given various interlocking shapes.

The object of the present invention is to provide an economical construction, which may be readily assembled as a whole initially or in part on repair, in which practically the full length of each brick unit is available for wear in use and in which each brick unit has integral suspending means external of its refractory portion whereby it may be supported in the roof assembly.

The invention is illustrated in the accompanyl ing drawing, in which Figure 1 is a perspective view of the brick unit with one form of support. Figure 2 is a side view of a somewhat modified form of the unit and support. I6 Figure 3 is a side view of another form of the brick unit.

Figure 4 is a plan view of the latter form. Figure 5 is an elevation view of a group of assembled units with supporting means. I 0 Figure 6 is an end view of the construction shown in Figure 5.

Figure 7 is an end view furnace construction.

In the drawing, I is a casing,

partly in section of a preferably of steel, into which is placed basic or neutral refractory material to form a compact refractory unit, constituting an unburned or chemically bonded brick, which may be at least temporarily supported therein by means of lnturned projections 3. Two sides of the casing are upwardly extended to constitute integral lugs l as shown in Figures 1 and 2 or, as shown in Figures 3 and 4, two side walls may be bent over the top of the refractory portionto constitute an integral. lug 4'. Portions of adacent sides may be inturned as at 5 for additional support. The casing l and the lugs 4 may be spot-welded or otherwise united'as desired. The lugs 4 and 4' may be perforated as at 6 to receive auxiliary supporting members 1 or 1" or the lugs 4 may be provided 6 with internal shoulders 8 to receive a supporting hook 9. The supports 7' and 9 are suspended on a bar Ill or other suitable means illustrated at H in Figures 5 and 6. If desired, the units I may be tapered as illustrated in Figure 2 for the 10 formation of an arch such as shown in Figure 7, in which individual units are suspended on the beam or bar I0 supported at the sides of the furnace.

In manufacture, the casing with its integral lugs is preformed and welded and the refractory is compactly placed therein as by hammering to insure formation within the casing of an unburned brick portion which, supported by the projections 3 and the casing, will withstand handling and transportation incident to assembly in a furnace. When subjected to operating temperatures in the furnace the refractory portion is burned progressively upwardly throughout its length (say 18") and the casing walls become, as it were, welded to and about the refractory core, insuring at the exposed face of the roof a surface having great resistance to Wear and spalling, yet retaining in each unit the suspending lugs so arranged that the full length of the re fractory brick portion is available for operating use in the furnace. The lifeof the roof is thus substantially prolonged and there is little waste of expensive refractory material. As portions of the roof, subjected to most severe conditions, becomeunfit for further use, the units in such portions may be removed, without tearing down the whole roof, and be replaced by new units with their integral lugs.

The unburned brick portion may be preformed, as by pressing, to simply fit within the casing in which it may be supported by the taper and/or by the inward projections 3. The preformed unburnedbrick may be provided with depressions to receive the projections 3. The supports, as In and II, may be pipes through which water may pass for cooling purposes. This makes it possible to use shorter and less expensive supporting hooks or members such as l or 9.

I claim:

1. In a furnace, a suspended roof construction comprising metallic suspending means, a sheath, and a shaped refractory unit therein, said sheath being open at its ends and formed of metal which at furnace operating temperature becomes ad- 1 said sheath is tapered at its lower end to provide means for retaining said refractory unit therein.

5. In a furnace, a suspended roof construction comprising metal suspending means, a sheath and a refractory brick in the sheath, said sheath being formed from metal adapted at operating furnace temperature to fuse to said brick and having two sides extended beyond the point reached by the top of the brick, said sides having their upper extremities adapted for connection to said suspending. means, and having means 1 wherein removed from the lower end of the sheath for securing the brick in the sheath.

6. In a. furnace, a suspended roof comprising a demountable hanger structure, a sheath formed from steel and'refractory material compactly disposed within the sheath, said sheath having at least one side which is longer than the body of said refractory material and which is disposed for attachment to said hanger structure and said sheath having means independent of its lower end for securing said refractory body therein.

7. 'In a furnace, a suspended roof construction, comprising a demountable hanger structure, a preformed metal casing, open at its ends and having integral therewith lug means projcttlng from one end thereof and formed for attach cut to said hanger structure, and in said casing a compactly formed unburned brick of neutral or basic refractory material, said metal casing being adapted under operating furnace conditions to become fused to said brick.

DANIEL WALLACE STEWART. 

